Kotzin disclosed an "audio-visual display device" in his U.S. Pat. No. 4,240,218 having a model rotatably held within a terrarium housing by securing the model on a capstan 48 which is jacketed in a bearing tube 46 and driven by a driving mechanism such as a musical device 50. However, the model capstan or shaft is pivotally mounted through a bottom plate of the housing and a water leakage may be caused through an aperture between the shaft and the casing.
Meanwhile, the model or creature is made as a fixed type to be lacking of vividness so that such a display device can not provide a better decorative effect to livingly mimic a sportsman's action.
The present inventor has found the drawbacks of a conventional display device and invented the present rotatably-twisting display device.